Showing posts with label antennas. Show all posts

VK3MO's 20 Element Monobander for 20 Meters!

 

Ian VK3MO was booming in from Australia this morning. No wonder: he has a 5 over 5 over 5 over 5 array on a rotatable tower.  He can get a 3 degree takeoff angle with this antenna and I think I heard him say that he is working on another so that he can get a one degree takeoff angle. He was also using a using a Collins 30L1 linear.  Lots of soul in that old machine!
 
At one point in our QSO, I turned off my .12 kW amplifier.  He said I was still 58-59 with 3-4 watts. 
 
And Ian is a homebrewer!   He has built a number of transceivers and has another one in the works.  I told him about the BITX and he printed out Farhan's article (to read later).   He tells me that he has heard Peter Parker, VK3YE, on the air. 
 
In this QSO, Ian was using a modern commercial rig, but wouldn't it be great if we could get him to connect a homebrew sideband rig to that big antenna.  Go for it Ian!



More on Ian's antenna here: http://vk6ysf.com/vk3mo_visit.htm


Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

More on VK6MV



Last week during the big St. Patrick's day solar eruption/CME impact I (with the help of the radio gods) managed to work Roy VK6MV in Western Australia. (A video of Roy working QRP pedestrian mobile stations in the UK appears above.)   Could it  have been that that miraculous contact was ALSO my first ever homebrew SSB to homebrew SSB QSO?   I e-mailed Roy to find out.   Alas, it was not.  But OM Roy sent some interesting info on his station and especially his antenna.  Excerpts from his e-mail:  

Hi Bill

Thanks for the qso and the email.

yes another 'fadeout' but we have had many over the years haven't we ?
Things have changed a lot since 1963 when I had my first license as G3SML.
We came to Aus in 1977 with 3 sons and now have 24 Grandies 13 Grandchildren; 11 Great Grandchildren.

I liked the early Plessey IC's when they came out ~
Carry on with home brew and get that personal enjoyment out of it, it gives you a boost I am sure.  NO I was not on the home brew I was on the Icom IC740 which I bought about 5 years ago at the WA Hamfest it had a fault of jumping to different frequencies, etc. I could not find its intermittent fault at all, but on the internet a 'W' ham in your country posted the same fault with explanations etc,
and it cured it,

So I was on that Rig + a home brew linear pair of old 813's in Grounded Grid and  a Voltage doubler for the + 2 kv,  I could not get the smoothing caps for that voltage so got hold of 3 metal canned ones 800 volt, then got some plastic drain pipe to insulate the cans from ground & then put them all in series with equalising resistors,
and it worked.

Yes I was on the rhombic ~ amazing antenna for a fixed point to point contacts ~
why a rhombic you may ask well when in the Uk I used to work VK2NN [and others] Tom with his farm of rhombics his setup much larger, and I thought one day I would love to put one up. Eventually with our moving to Aus' then came down here with its 8+ acres the opportunity led itself to put one up, and as I used to work into Europe/UK a lot that direction picked. first I put one up a bigger one than now,  but it did not work that good.  Moral the longer you go the higher it needs to be
So a smaller version tried using the contours of the land at a height above sea level of 1260 feet asl helps. Using 12 gauge usa hard drawn copper wire   I needed winches and turnbuckles etc to pull it up, one end is on the 60 ft tower, the others on assorted Wooden Poles +
The termination R for the rhombic is a 3 element TH3 Tribander ~
think of it why waste power into a whopper of a Resistor ~
this is not my idea but came from ~ Nano VK6UN why not connect it to another antenna with how to do it came from now SK Les Moxon G6XN
a clever man how to make a balun out of old ferrite rods from transistor radios,

Will close now my half a dozen lines of text are expanding to much

Cheers have fun Roy VK6MV


Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Kirk's Herring Aid, Tuna Tin, and Regen Adventures

 
Hello Bill!
 
Just a quick hello from MN to tell you how much I have been enjoying your podcast. Although I have "plugged" your stuff in multiple magazine columns over the years, I'm a bit late getting into the listening game. My current contract job has me doing a lot of driving, however, so I now have several years' worth of soldersmoke to enjoy.
 
Several of the most recent episodes have made it clear that we have covered some common ground in our amateur radio careers.
I was licensed in 1977 at age 15 -- a year after I built my Tuna Tin 2 :) The transmitter was a smashing success. I used it with my Tempo One transceiver, or at the electronics repair shop at a local National Guard base (where my mom worked as a civilian administrator). I would ride my bike to Camp Ripley (only 8 miles or so), and the guys in the signal shop would let me use the shop's Collins KWM-2 HF transceiver (and attached dipole). Other than my efforts, I don't think the KWM-2 got much use...
 
I, too, tried to get the Herring Aid 5 to work, with no luck at all. Listening to your podcast was like being in a time machine of sorts :) I wonder if I got the "sense" of the oscillator secondary messed up? I never did get that thing to make even a sound. I don't have it any longer. The same goes for the TT2. They got "lost" when I stored a bunch of stuff at my dad's place in-between moves, as did a home-brew 4-400A amplifier and a 6146B amplifier for my Ten-Tec Argonaut. Darn!
 
Don't forget about the matching VFO -- the Chopped Beef Slider (CB Slider), which was built into a chopped beef can, of course! I didn't build one, but as I recall it was a diode-tuned 40-meter VFO for the TT2.
 
Your "regen rage" and its subsequent easing was also amusing. I have had a love-hate relationship with those buggers, too, although mine was mostly love. You referenced Dave Newkirk's (now W9VES) 40-meter QST regen article in a podcast. I was fortunate enough to be a QST editor at the time Dave was in his "second residence." That guy forgot more about receivers than I will ever know, and he helped me tremendously in official and unofficial capacities.
I have attached a photo (above) of a multiband regen that Dave helped me build (he designed and dispensed wisdom while I built the radio). He took a schematic from a 1930s ARRL Handbook and tweaked it a bit, helping me add a VR tube, "more modern" tubes and a few other goodies. Just to be difficult, I sampled the tank circuit with a tiny-value capacitor and a high-gain MMIC amplifier so I could drive a frequency counter, which displayed the receive frequency as long as the tank was oscillating. It was fun, but it was difficult to isolate the digital noise from the counter, so I only really turned on the counter as necessary, or to calibrate a dial, etc. The chassis used to be an Eico audio signal generator... In the photo the Jackson Brothers dial and bezel/tuning scale isn't completely installed. After sitting in a box for 25 years, the regen still works but probably needs new tubes, as it's rather deaf :) Blasphemy aside, I'm moving on to solid-state regens...
 
I, too, just got a Rigol DSO. Wow, the "one-button" measurement is almost too easy.
 
I'm prepping my book, Stealth Amateur Radio, for release on the Kindle (and maybe other e-book formats), but it's available now from my website, www.stealthamateur.com.
 
Keep up the good work, Bill.

I'll be listening. :)

73,

--Kirk Kleinschmidt, NT0Z
  Rochester, MN

Editor, 1990 ARRL Handbook
Technical Editor, Ham Radio for Dummies
QST Assistant Managing Editor, 1988-1994
Ham Radio Columnist since 1989 for:
   Popular Communications
   Monitoring Times and now,
   The Spectrum Monitor (www.thespectrummonitor.com)
My book, "Stealth Amateur Radio," is now available from
www.stealthamateur.com and on the Amazon Kindle (soon)

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

DuWayne's AD9850 Arduino TFT SWR Scanner



This is really nice.   DuWayne KQ4VB, has been talking to Pete about his use of digital chips, Arduinos and TFT displays in homebrew SWR analyzers.   Obviously these techniques could be used to measure the passband of crystal filters.  (Far superior to my pencil and paper procedures.)  Nice work DuWayne!


Pete
Looks good, I did some playing with the TFT board I have.  Did a board for the antenna analyzer using the TFT and a 9850 DDS module insted of the NOKIA and si5351.  Wanted to see if there was much difference between a sine wave out and the square wave from the 5351.  Appears to be very nearly the same from a couple of quick tests I have done.  Want to try some different diodes and change some values for amplifier gain.
Will keep you informed. DuWayne

Earlier... (4 November 2014)

Pete
Really enjoy listening to you on Solder-Smoke.  Saw the link to your
xcvr with the Adafruit si5351 board.  I got a couple of them and have
been playing with code for them.  Have been spending most of my time
working on an antenna analyzer based on the one by K6BEZ. Pleased to see
your article in the latest QQ.  I have used basically the same circuit,
except am using  the little NOKIA LCD display. The resolution is not the
greatest  but works well for this application.  I am using some of the
original code from K6BEZ to talk with his existing PC program.  For
stand alone I have 2 modes, a straight tune mode where I can select the
frequency and read the SWR.  Also implementing a sweep mode that scans
the whole band and after it is finished you can tune across and see the
frequency and SWR.  I am attaching a couple of pictures of what I have
so far. Waiting on the correct op amp to arrive and making some changes
to the amp gain to get better results on the higher band where the
output of the DDS drops off.
Thanks for all the inspiration you give to us home builders and tinkerers
out here.
73 DuWayne   KV4QB


Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

SolderSmoke Podcast #170 Double A DX-pedition, SI5351, Mighty Mites, Phasing Dreams


SolderSmoke Podcast #170 is available: 

http://soldersmoke.com/soldersmoke170.mp3

Bill's Double A, DSB, Dipole, Dominican DX-pedition.  
             Living the "How's DX?" Dream
Seeing the Southern Cross with Soviet Binoculars
Pete goes remote 
SI5351 a chip with a lot of potential
Pete's experiments with Nokia LCD displays 
Michigan Mighty Mites around the world
               The Postal Stream Roller
Steve Silverman's very kind variable cap offer
MOXON modeling with EZNEC
Aspirations for 2015

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Moonlight Moxon





Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Moxon Aloft!



We put it up on the roof this afternoon.  I think it looks great!   The neighbors have not yet risen up in opposition to the new skyhook.   My family thinks it cool that I can spin it around.   I have it pointed at Europe and I notice a big difference.  I've worked F5LIW, OT4A, YL2BJ,  F5BBD.  Lots of fun. 



Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Scrap wood, some wire, four fishing poles and an old tripod: Moxon Update

 
It is not up on the roof yet, but we are getting close.   Above you can see he center "hub" -- just some scrap plywood and 8 u bolts.


 
Here is how I handled the corners.  The coil thing is from the end of a bungee cord. It makes for easy disassembly. 

 
 
 
Here is how the mast connects to the hub.  I had some 1x1 scrap wood. The 1x1 will be U-bolted into the rotator.  


 
 


 
Made of wire and fishing poles, Moxons are not very photogenic.  But I think mine looks great.  The 17 meter version is quite small. 
 


 
A bit of a balun.  Just to keep RF currents off the outside of the braid.
 



 
That tripod was last aloft in the Dominican Republic (1992-1996!).  Two spray cans of flat black paint have been applied.  Stealth!  

 
Four 16 foot "crappie" telescoping fiberglass poles purchased from Amazon.   

 
The only thing holding me up at this point is a safety concern.  The roof has a somewhat steep pitch, and I am not at agile as I used to be.   So before I install this magnificent sky hook I'm getting one of those roof safety harness systems that roof workers are supposed to use (but rarely do).  This sill also benefit the poor fellow who comes to clean our gutters.  



Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

MOXON Antenna Project -- Need Rotator Advice

 
 
I've been put together a fishing pole MOXON antenna for 17 meters.  It will be used with my 5 Watt BITX rig.  I need something to spin it around.   I know that many of the cheap TV rotators don't hold up very well.  I had one die quickly out in the Azores.  There seems to be several brands out there, but the rotators and the control boxes look suspiciously similar. 
 
Is there any brand out there that is more robust and reliable than rest? 


I came up with a pretty cool way of affixing the corners of the antenna elements to the fishing poles.  That coil-like thing is the wire part of a bungee cord.  It fits nicely into the end of the fiberglass pole. You have to be sure to get the pole length and the element dimensions properly proportioned, with a sufficient amount of bend in the poles.

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Alan Wolke's GREAT Video on Transmission Line Termination



An outSTANDING Wave video from Alan!  Check out the comments from new hams on the YouTube page:  Alan has a real knack (!) for explaining technical material, and for imparting real understanding. 

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

Latest Project: 17 Meter Moxon


17 Meter Moxon by AE6AC

That's what I have in mind.  I ordered four fiberglass "crappie" poles yesterday.  I have a tripod for the roof.   What should I use to spin this thing around?  A TV rotor is an obvious solution, but the last time I used one it didn't hold up too well.  There is always the Armstrong method...  

Here's AE6AC's site:

http://www.moxonantennaproject.com/ae6ac/ae6ac.htm


Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

The Jamesburg Dish


Mama mia!  That's an antenna!  This is the skyhook that the very hip people in yesterday's video (scroll down) are using to send very cool messages to Gliese 526.  With a setup like that, they may have a shot at a QSO!  

More on the antenna here: http://www.jamesburgdish.org/

As I suspected, real hams (not the hipsters!) are doing the tech work. 
 
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20